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for-in iteration with and without cache
(version: 0)
Comparing performance of:
No cache vs Cache
Created:
7 years ago
by:
Guest
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Tests:
No cache
const object = {}; for (let i = 0; i < 1000000; i++) { object[i] = i; } for (const key in Object.keys(object)) { object[key]++; }
Cache
const object = {}; for (let i = 0; i < 1000000; i++) { object[i] = i; } const keys = Object.keys(object); for (const key in keys) { object[key]++; }
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Suite status:
<idle, ready to run>
Run tests (2)
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Result
No cache
Cache
Fastest:
N/A
Slowest:
N/A
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Autogenerated LLM Summary
(model
llama3.2:3b
, generated one year ago):
Let's break down the benchmark and explain what's being tested. **Benchmark Overview** The test consists of two individual test cases: "No cache" and "Cache". The primary focus is on comparing the performance of two approaches to iterate over an object in JavaScript. **Options Being Compared** There are two main options being compared: 1. **For-in iteration without caching**: In this approach, the code uses `for (const key in Object.keys(object))` to get an array of keys from the object and then iterates over it using a traditional for loop. 2. **For-in iteration with caching**: In this approach, the code uses `Object.keys(object)` to directly iterate over the keys of the object without getting an array. **Pros and Cons** * **Without caching (No cache)**: + Pros: Can be more efficient if the object is large because it doesn't create a new array of keys. + Cons: Requires extra memory allocation for the `Object.keys(object)` call, which can lead to performance issues in some cases. * **With caching (Cache)**: + Pros: Creates a new array of keys only once and stores it in a variable, making subsequent iterations more efficient. + Cons: Requires an extra step to get the array of keys, which can introduce overhead. **Additional Considerations** * The test uses JavaScript's `Object.keys()` method, which returns an array-like object containing the enumerable property names of an object. This allows for direct iteration over the keys without creating a separate array. * Both test cases use a similar loop structure: a traditional for loop with a variable incrementing from 0 to the length of the object. **Library or Special JavaScript Feature** None are mentioned in this benchmark. Now, let's look at some alternatives: Alternatives to this benchmark could include comparing other iteration methods, such as: * Array.prototype.forEach() * Loops using `Array.from()` and `forEach()` * Using a library like Lodash's `mapKeys()` function However, these alternatives would require significant changes to the test cases and might not accurately represent common use cases. Overall, this benchmark provides a simple yet informative comparison of two iteration approaches in JavaScript.
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TestKey
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